[jdk21u-dev] RFR: 8341978: Improve JButton/bug4490179.java

[Goetz Lindenmaier]

I backport this for parity with 21.0.7-oracle.

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Commit messages:
 - Backport 8174cbd5cb797a80d48246a686897ef6fe64ed57

Changes: https://git.openjdk.org/jdk21u-dev/pull/1243/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1243&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8341978
  Stats: 88 lines in 1 file changed: 66 ins; 3 del; 19 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1243.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1243/head:pull/1243

PR: https://git.openjdk.org/jdk21u-dev/pull/1243